MADRID (Reuters) - Radioactivity from a leak detected at Spain’s Asco I nuclear power plant during refueling last November was below legal limits, Spain’s nuclear watchdog said on Tuesday.
The Nuclear Safety Commission sent inspectors to the plant after being told on Friday that a routine inspection had detected radioactive particles on the outside of buildings at Asco I, in the northeast Catalonia region.
Environmental group Greenpeace on Saturday said it had information that radioactivity levels were “significant” and protested about the delay in detecting contamination from the leak and making the information public.
Spain’s Socialist government has pledged to close down the country’s eight nuclear power stations and the country has become a leading producer of electricity from renewable sources like wind and solar power.
Asco I is a pressurized water reactor (PWR) and is wholly owned by Spain’s second largest utility Endesa. It was opened in August 1983 and its operating permit is due to expire in 2011.
The CSN said in a statement that particles were found in patches, rather than being uniformly spread around the plant, and consisted of cobalt-60 and manganese-54, amongst other materials.
It added that total radioactivity detected was about 235,000 becquerels (Bq), or below a legal limit of 320,000 Bq for radioactivity from cobalt-60 ingested by a member of the public.
“These results show that the radioactive impact of the event on workers, members of the public and the environment is well below established regulatory limits,” the CSN said.
Cobalt-60 is produced when materials like steel absorb radioactivity from reactors, according to the U.S. Environmental Protection Agency. It has medical uses, like radiotherapy, but can be dangerous as it emits gamma rays, exposure to which over time can cause cancer.
Although the leak happened in November, particles were not detected outdoors until March 14, when checks were stepped up.
Greenpeace charged the CSN with downplaying the leak and only making it public after the environmental group protested.
It also disputed the CSN’s conclusion that exposure to radioactivity was within legal limits, saying that readings had been taken months after the leak, in which time radioactive materials would have decayed or been dispersed.
The CSN said its president, Carmen Martinez, had asked to give evidence to the Spanish parliament.
Reporting by Martin Roberts; Editing by Daniel Fineren